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Weirong Fang Rui Zhang Lan Sha Peng Lv Erxin Shang Dan Han Jie Wei Xiaohan Geng Qichuan Yang Yunman Li 《Journal of neurochemistry》2014,128(5):662-671
The blood–brain barrier (BBB) greatly limits the efficacy of many neuroprotective drugs' delivery to the brain, so improving drug penetration through the BBB has been an important focus of research. Here we report that platelet activating factor (PAF) transiently opened BBB and facilitated neuroprotectant edaravone penetration into the brain. Intravenous infusion with PAF induced a transient BBB opening in rats, reflected by increased Evans blue leakage and mild edema formation, which ceased within 6 h. Furthermore, rat regional cerebral blood flow (rCBF) declined acutely during PAF infusion, but recovered slowly. More importantly, this transient BBB opening significantly increased the penetration of edaravone into the brain, evidenced by increased edaravone concentrations in tissue interstitial fluid collected by microdialysis and analyzed by Ultra‐performance liquid chromatograph combined with a hybrid quadrupole time‐of‐flight mass spectrometer (UPLC‐MS/MS). Similarly, incubation of rat brain microvessel endothelial cells monolayer with 1 μM PAF for 1 h significantly increased monolayer permeability to 125I‐albumin, which recovered 1 h after PAF elimination. However, PAF incubation with rat brain microvessel endothelial cells for 1 h did not cause detectable cytotoxicity, and did not regulate intercellular adhesion molecule‐1, matrix‐metalloproteinase‐9 and P‐glycoprotein expression. In conclusion, PAF could induce transient and reversible BBB opening through abrupt rCBF decline, which significantly improved edaravone penetration into the brain.
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Artesunate exerts an anti‐immunosuppressive effect on cervical cancer by inhibiting PGE2 production and Foxp3 expression 下载免费PDF全文
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Wei Gao Yongxun Jin Jindong Hao Siyi Huang Dongxu Wang Fushi Quan Wenzhi Ren Jiabao Zhang Mingjun Zhang Xianfeng Yu 《Molecular reproduction and development》2021,88(1):55-66
Oxidative stress negatively affects the in vitro maturation (IVM) of oocytes. Procyanidin B1 (PB1) is a natural polyphenolic compound that has antioxidant properties. In this study, we investigated the effect of PB1 supplementation during IVM of porcine oocytes. Treatment with 100 μM PB1 significantly increased the MII oocytes rate (p <0.05), the parthenogenetic (PA) blastocyst rate (p <0.01) and the total cell number in the PA blastocyst (p < 0.01) which were cultured in regular in vitro culture (IVC) medium. The PA blastocyst rate of regular MII oocytes activated and cultured in IVC medium supplemented with 100 and 150 μM PB1 significantly increased compared with control (p < 0.01 and p < 0.05). We also evaluated the reactive oxygen species (ROS) levels, mitochondrial membrane potential (Δψm) levels, glutathione (GSH) levels, and apoptotic levels in MII oocytes and cumulus cells following 100 μM PB1 treatment. The results showed that the PB1 supplementation decreased ROS production and apoptotic levels. In addition, PB1 was found to increase Δψm levels and GSH levels. In conclusion, PB1 inhibited apoptosis of oocytes and cumulus cells by reducing oxidative stress. Moreover, PB1 improved the quality of oocytes and promoted PA embryo development. Taken together, our results suggest that PB1 is a promising antioxidant additive for IVM of oocytes. 相似文献
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国产7种乌头属植物的核型研究 总被引:7,自引:0,他引:7
本文报道了国产7种乌头属植物(两色乌头(Aconitum alboviolaceum Kom.,牛扁 A.barbartum var.puberulum Ledeb.,蔓乌头A.volubile Pall.,展毛蔓乌头 A.ciliare DC.,北乌头 A.kusnezoffii Reichb.,蒿叶乌头 A.artemisiaefolium Bar.et Skv.,细叶乌头 A.macrorhgnchum Turcz.)的核型。其中展毛蔓乌头、蒿叶乌头和细叶乌头的核型为首次报道。本文还首次指出乌头属中具多年生根状茎的牛扁亚属植物的核型没有明显的二型性,而具二年生块根的乌头正属植物的核型的二型性十分明显。此外还讨论了细叶乌头及展毛蔓乌头的系统位置,认为它们与蔓乌头有较近的亲缘关系。 相似文献
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湛江高桥红树林和盐沼湿地的大型底栖动物次级生产力 总被引:2,自引:0,他引:2
为了比较湛江高桥潮间带不同植物生境的大型底栖动物次级生产力,根据2010年4个季度湛江高桥潮间带生境的大型底栖动物数据,运用Brey经验公式计算不同植物生境的大型底栖动物次级生产力.结果表明:湛江高桥红树林和盐沼湿地不同生境大型底栖动物平均次级生产力为11.77 g AFDM·m-2·a-1.其中,无瓣海桑生境次级生产力最高,为18.16 g AFDM·m-2·a-1,其次是桐花树、盐地鼠尾粟和木榄生境,分别为17.67、8.34和2.92 g AFDM·m-2·a-1.在4种生境中,木榄生境的年生产力/年均生物量(P/B)最高,为2.38,其次是无瓣海桑、盐地鼠尾粟和桐花树生境,分别为1.23、0.99和0.48.湛江高桥潮间带不同植物生境大型底栖动物次级生产力和P/B值的差异主要与总有机碳含量、食物类型和动物个体大小有关. 相似文献
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